Question

In paddy fields, blue-green algae are grown ?

• A. For medicinal uses
• B. To increase soil fertility
• C. To serve as food for fishes
• D. To conserve water

Answer 1

The correct option is B To increase soil fertility

Cyanobacteria (Blue-Green Algae) are free-living photosynthetic nitrogen fixers. They are one of the major components of the nitrogen fixing biomass in paddy fields. They grow on the surface of paddy field soil and enriched it with a good source of nitrogen. They help in maintaining the soil fertility, consequently increasing rice growth and work as a natural biofertilizer.

Thus, the correct answer is option B.